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Financial Instruments (Narrative) (Details) lb in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) lb | Dec. 31, 2022 USD ($) lb
Derivative [Line Items] |  |
Weight of aluminum that hedged future purchase of aluminum to meet fixed-price forward sales contract obligations, lbs | lb | 5.6 | 20.3
Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar | $ 139.0 |
Amounts of unrealized after-tax gains on derivative instruments | 0.8 |
Aluminum Futures Contracts |  |
Derivative [Line Items] |  |
Derivative, Notional Amount, Net | $ 7.7 | $ 30.7

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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480870/815-30-50-1 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
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- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
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